Re: SSHD: Limit login attempt rate

bmearns wrote:
Thanks for all the great recommendations. I'm especially interested in
iptable rate-limiting and port-knocking, which I will be looking more
into.

With SuSE Linux iptables. Change the line numbers (21 and 22) to your needs:

# iptables --insert input_ext 21 -p tcp -m state --syn --state NEW --dport 22 -m limit --limit 1/minute --limit-burst 2 -j ACCEPT
# iptables --insert input_ext 22 -p tcp -m state --syn --state NEW --dport 22 -j DROP

Works here.

Günther
.